Autori: Valentina Anuta, Lavinia Hinescu, I. Mircioiu, Monica Soare-Rada, Cristina Ranetti, N. Soldan, M. Ionescu, E Ionica
Editorial: 13th Congress of Balkan Military Medical Committee, p.p. 141, 2008.
Aim of the study. Development and validation of a sensitive, reproducible HPLC quantitative method for determination of diltiazem and desacetyldiltiazem in human plasma.
Material and method. After extraction from plasma with tert-butyl methyl ether and back-extraction into 0.025N phosphoric acid, analytes were measured by reversed-phase HPLC on a C18 column at 235 nm.
The separation was performed on a Ascentis C18 (150*2,1 mm), at 0.3 mL/min flow rate and a temperature of 35°C. The mobile phase consisted of a 0.025M potassium dihydrogen- phosphate buffer containing 0.2% triethylamine (pH=2.2)- acetonitrile (72:28 v/v) mixture. Haloperidol was used as internal standard.
Results. Studies were performed in order to select the optimum mobile phase composition, extraction technique, internal standard for the analysis and in order to evaluate pH range of maximum stability for all analytes.
The selected method proved to be selective and linear for analytes concentrations ranging between 1.25 and 250 ng/ml for desacetyldiltiazem and 2.5 and 500 ng/mL for diltiazem. The mean recovery from plasma was 96.5% for metabolite and 105% for the parent drug, while the within and between day coefficient of variation and percent error values of the assay method were all less than 9 %.
Conclusion. The method was used and proved tobe adequate for evaluation of diltiazem and desacetyldiltiazem pharmacokinetic in humans, after oral administration of 120 mg diltiazem.
Cuvinte cheie: Diltiazem, Desacetyldiltiazem, HPLC